Wolf signed it Thursday, despite opposition from most of his fellow Democrats in the Legislature. It takes effect in 60 days.

The bill eliminates exceptions in current law that had permitted those acts during labor disputes, but it keeps exemptions for “constitutionally protected activity.”

It completely eliminates an exception for threatening to use weapons of mass destruction.

The Republican sponsor, Rep. Ron Marsico, says peaceful labor activity won’t be affected and that labor disputes shouldn’t be held to different standards. Democrats had warned that it could chill the free speech rights of union members.

The law drew renewed attention after some members of a Philadelphia Ironworkers union were charged with racketeering and arson last year.